Perspective transform revisited

[Ottia Tuota]

(12-03-2020, 02:17 PM)denzjos Wrote: Nice job Ottia Tuota. Just used it on another clock and the result is OK. Tried it on a flange drawing and the result is NOK. Any suggestions? Thanks in advance.

Clock OK


Flange NOK

Thanks for trying the plugin. I changed the path slightly and got a quite satisfactory result. See the attached file:


  flange_big_test2.xcf (Size: 317.62 KB / Downloads: 262)

The strokes with 2 and 3 anchors: I moved the anchors a little to get them on the inner ellipse as closely as possible.

The stroke with 1 anchor: I changed the diagonals slightly at the top since it seemed to me that the top guide was a little too high. I changed the center point accordingly. (By the way, you had a neat trick to find the center!)

I didn't look into it any further, so I don't know which changes were the most significant. But it seems that the process is very sensitive on the exact placing of the anchors. But that is no fault of the plugin. Rather, it is a feature of the projective transformation (or of the transformation, whatever it is, that is done by that Gimp's inner procedure).